AT Protocol MCP Server

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track_users ​

Track activity from specific users in the firehose stream. Returns recent events from the specified users.

Authentication ​

Optional - This tool works without authentication but requires the firehose to be started first using start_streaming.

Parameters ​

ParameterTypeRequiredDefaultDescription
usersstring[]Yes-Array of user DIDs or handles to track. At least one user is required.
limitnumberNo20Maximum number of events to return. Must be between 1 and 100.
eventTypesstring[]No['post']Types of events to track. Options: post, like, repost, follow, profile.

Response ​

typescript
{
  success: boolean;
  users: string[];
  events: Array<{
    user: string;
    eventType: string;
    collection: string;
    operation: string;
    record?: any;
    seq: number;
    time: string;
    receivedAt: string;
  }>;
  totalEvents: number;
  totalScanned: number;
}

Examples ​

Track User Posts ​

json
{
  "users": ["alice.bsky.social"],
  "limit": 10
}

Track Multiple Users (All Event Types) ​

json
{
  "users": ["alice.bsky.social", "bob.bsky.social", "did:plc:xyz123"],
  "limit": 50,
  "eventTypes": ["post", "like", "repost", "follow"]
}

Track User Engagement Only ​

json
{
  "users": ["influencer.bsky.social"],
  "eventTypes": ["like", "repost"],
  "limit": 25
}

Error Handling ​

Common errors:

  • InvalidRequest: No users provided or invalid parameters
  • StreamingNotStarted: Firehose streaming must be started first using start_streaming
  • RateLimitExceeded: Too many requests in a short period

Best Practices ​

  1. Start Streaming First: Always call start_streaming before using this tool
  2. Use DIDs for Reliability: DIDs are permanent, handles can change
  3. Filter Event Types: Specify only the event types you need to reduce noise
  4. Adjust Limit: Start with a smaller limit and increase as needed
  5. Buffer Size: The tool scans the event buffer, which has a maximum size - older events may be dropped
  6. Track Key Accounts: Monitor influential users or competitors for insights
  7. Combine with Keywords: Use monitor_keywords alongside this tool for comprehensive monitoring

Event Types ​

  • post: New posts created by the user (collection: app.bsky.feed.post)
  • like: Posts liked by the user (collection: app.bsky.feed.like)
  • repost: Posts reposted by the user (collection: app.bsky.feed.repost)
  • follow: Users followed by the user (collection: app.bsky.graph.follow)
  • profile: Profile updates (collection: app.bsky.actor.profile)

Rate Limiting ​

This tool reads from the local event buffer and is not subject to AT Protocol API rate limits. However, the firehose connection itself has limits:

  • Maximum 1 concurrent firehose connection per client
  • Event buffer size is limited (typically 1000 events)
  • Older events are dropped as new ones arrive

See Also ​